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App inventor 2 en español
Cómo programar los teléfonos móviles con Android
mediante App inventor 2 - Juan Antonio Villalpando

-- Tutorial de iniciación de App Inventor 2 en español --

Volver al índice del tutorial


- Archivos apk.

5.- Definite Integral



6.- Moon phase
. Moon age.


 fasesdelaluna.zip (images)



9.- Calculates the linear equation given two points.


10.- Draw Archimedean spiral.


11.- Parity bit.


12.- Pully on an incline with friction.

A 5 kg mass is placed on an incline with friction. Making an angle of 30 degrees with the horizontal. A rope is attached and positioned over a pulley at the top of the incline. A 6 kg mass is suspend from the free end. What is the acceleration of the system.
m1 going up or down?
Assume µ = 0.20


13.- Uniform Rectilinear Motion.

A green car starts and maintains a speed of 90 km/h in a straight line.
Another red car located 24 km, starts 2 hours later at a speed of 120 km/h
Calculate how long it will take to reach the green car.


14.- Find the Inverse of a Given Number.
Show number and result with multiples and submultiples prefix.


15.- Circuit RLC, calculate the impedance Z.



16.- Wheatstone bridge.


a) Create a random value for Rx.
b) Move the Slider until the volts are approximately zero.
c) Now Rx = R * (R2 / R1)



18.- Prime number decomposition.


19.- Statistical.


In a class of 18 students, they have obtained the following scores: 4,4,4,5,5,5,5,5,7,7,8,8,8,8,9,9,9,10.

Calculate the mean, variance and standard deviation of that distribution.

20.- Minimum cylinder surface.

20.- An open-topped cylindrical container has a volume of V = 3140 cm3. Find the cylinder dimensions (radius of base r, height v) so that the least material is needed to form the container.
From: https://www.hackmath.net/en/math-problem/5891?tag_id=91&result=1


21.- Maximun angle.

21.- The Statue of Liberty measures 46 m, is 47 m above ground level, look image.

What distance should one stand away from the statue in order to maximize the view of the statue? That is, what is the maximum angle Θ.


  • Build an application using the expressions above.
  • And with a slider change value of x, get Θ and check the maximum angle Θ, in this case Θ = 19.18209º to x = 66.1 m

- Information: https://www.slideshare.net/leingang/lesson-20-more-optimization-problems (pag. 20)

- apk file in external link: http://kio4.com/appinventor/apk_archivos.htm

22.- Law of cosine.


teorema_cosenos_i.aia (unfinished)

In a right triangle we can calculate the c side using the Pythagorean theorem.

If the triangle is not a rectangle, we can calculate the c side using the Law of Cosine.


Build an application where you can change sides a and b and the alpha angle using Sliders and get side c. Draw the triangle.

23.- Exponential regression.


p84F2_regresion_exponencial_i.aia (unfinished)

- Create an application to obtain the expression of an ab-exponential and e-exponential regression.

- ab-Exponential regression

You can get information about the ab-exponential regression in:


- e-Exponential regression

You can get information about the e-exponential regression in:



78.- Compare two colors. Average color of an image. Code proposals

1.- Vector color 3D.


2.- Compare color RGB. Method difference between RGB vectors.


3.- Compare two colors using the following algorithm.


4.- Using three Sliders create a color and compare it to the PH color scale. (use the method from the previous exercise.)


5.- Get average color of an image.


6.- Find the crossing point of two lines perpendicular to two sides of an equilateral triangle.



28.- Pixelates an image with dots.


- Divide an image into rectangles. Get the color of 4 random points in each rectangle.
- Find the average color of those points. Draw a point corresponding to that rectangle on another Canvas.



- Mi correo:
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